In terms of tactics, loadouts, and abilities, the current AI is near the best it's ever been, except for bugs.
Unless it's one of those high-threat opt-in encounters (wing assassinations/massacres, pirate activities, thargoids, CZ Spec Ops, etc), I generally don't need any Engineering at all to defeat a wing of ships similar to the one my CMDR is flying. Obviously Engineering makes things a lot faster though.
Doing missions and dropping into the odd HGE that shows up on the way to or from those missions is where my CMDR gets the overwhelming bulk of his materials and data from.
Yes.
While I still enjoy the game greatly, I think most major updates, with the possible exception of vanilla Horizons (2.0), have been one step forward, two steps back.
Neither Engineering, nor most supposed QoL changes, have really improved the experience for me.
An Elite NPC in the same ship as my CMDR simultaneously should always have had, never actually has had, and probably never will have, a significant chance of besting my CMDR.
I completely agree that NPC kills per hour have increased and completely understand that this feels like a nerf to some.
I just don't think we ever should have been able to measure our abilities against NPC combat vessels in terms of kills per hour. My CMDR has at least ten, and probably closer to a hundred, times the number of NPC kills as I'd consider plausible in any well-conceived and executed system.